FIG. 5 shows a prior art orthodontic bracket. In the figure reference numeral 1 indicates a main body of the bracket, which is made of a rigid substance having a fixed form against orthodontic force transmitted through an arch wire. Tie wings 3 necessary at ligating the arch wire are disposed on this bracket.
However in such a prior art bracket structure having tie wings, since the tie wings 3 are attached on occlusal and gingival sides of the main body of the bracket 1, food residue stagnates often inside the tie wing, which gives rise to gingivitis or halitosis.
Further there was often danger that a finger was wounded by a cut end of a ligature wire while ligating the wire against the tie wings 3, which led to inside infection among medical workers.
In addition, the tie wings on the occlusal side collided sometimes with opposing teeth and also for teeth in the course of eruption the tie wings on the gingival side were brought into contact with gingiva, which prevented to mount the bracket at a suitable position.